1. Field of the Invention
The present invention pertains to a housing arrangement for a friction clutch, especially for a multi-disk clutch, where the housing arrangement is designed in the approximate shape of a cup with a bottom area and an edge area intended for connection to a flywheel arrangement, and where at least one air through-opening is provided in the bottom area.
2. Description of the Related Art
A housing arrangement of this type is known from U.S. Pat. No. Des. 335,290. This known housing arrangement is designed essentially in the form of a cup and has several openings in the edge area, through which fastening screws can be inserted and screwed to a flywheel or the like. In the bottom area of the housing arrangement, several openings are provided, through which air can enter the interior of a friction clutch equipped with this type of housing arrangement.
It is the object of the present invention to provide a housing arrangement for a friction clutch which results in a friction clutch with improved operating characteristics.
According to the present invention, this object is achieved by a housing arrangement for a friction clutch, especially for a multi-disk clutch, where the housing arrangement is designed approximately in the shape of a cup and is provided with a bottom area and with an edge area intended for connection to a flywheel arrangement, and where at least one air through-opening is provided in the bottom area.
It is also provided in accordance with the invention that an edge area which forms the boundary at the front, with respect to an operating direction, of the minimum of one air through-opening is offset toward the interior of the housing with respect to an edge area which forms the boundary at the rear, with respect to an operating direction, of the minimum of one air through-opening.
As a result of the offset of the two edge areas forming the front and rear boundaries of the air through-opening in the manner according to the invention, it is ensured that, during rotational operation of the clutch, air is forced by a turbine-like effect into the interior space enclosed by the housing arrangement. The components present in the interior of the friction clutch, which are exposed to severe thermal loads as a result of friction, are therefore cooled more effectively.
To facilitate the entry of air into the interior of the housing, in the area of the front edge, the exterior surface of the bottom area of the housing arrangement slopes down toward the air through-opening and also toward the interior of the housing. As a result of this downslope of the exterior surface of the housing arrangement toward the air through-opening, a negative pressure is produced during rotational operation, which induces a suction effect.
The inward-flow action can be improved by allowing the interior surface of the bottom area of the housing arrangement in the area of the rear edge to slope upward toward the air through-opening and toward the exterior of the housing.
So that an essentially uniform distribution of the air inflow can be ensured, it is proposed that a plurality of air through-openings be provided in a row in the circumferential direction around an axis of rotation. Several groups of air through-openings can be provided.
The housing arrangement according to the invention can, for example, be produced by a casting process. In this case it is preferable for the housing arrangement to be out of balance before it is assembled with other components. When a pressure plate assembly or a friction clutch is fully assembled, several components are attached to various points on the circumference of the housing arrangement; these components do not necessarily find opposing bodies at some other point on the circumference to correct the imbalance. This is usually compensated by the attachment of additional balancing weights. By taking the approach according to the invention and installing air through-openings in the housing arrangement, it is possible, by taking appropriate design measures, to ensure that, first, the housing arrangement is not balanced in and of itself, and that, second, after the other components have been added, an assembly is obtained which has no imbalance in and of itself with the exception of those resulting from manufacturing tolerances.
In addition, it is possible in the housing arrangement according to the invention for an edge area forming the rear boundary, in the operating direction, of the leading air through-opening and the edge area forming the front boundary, in the operating direction, of the trailing air through-opening to be formed on a web area separating the two air through-openings from each other and for a surface of the web area facing the interior of the housing and/or a surface of the web area facing the exterior of the housing to be slanted with respect to a plane orthogonal to an axis of rotation.
The present invention also pertains to a friction clutch which comprises a housing arrangement according to the invention.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.